Article

Segregating variation in the transcriptome: cis regulation and additivity of effects.

School of Integraive Biology, University of Illinois, Urbana, Illinois 61801, USA.
Genetics (impact factor: 4.01). 08/2006; 173(3):1347-55. DOI:10.1534/genetics.105.051474 pp.1347-55
Source: PubMed

ABSTRACT Properties of genes underlying variation in complex traits are largely unknown, especially for variation that segregates within populations. Here, we evaluate allelic effects, cis and trans regulation, and dominance patterns of transcripts that are genetically variable in a natural population of Drosophila melanogaster. Our results indicate that genetic variation due to the third chromosome causes mainly additive and nearly additive effects on gene expression, that cis and trans effects on gene expression are numerically about equal, and that cis effects account for more genetic variation than do trans effects. We also evaluated patterns of variation in different functional categories and determined that genes involved in metabolic processes are overrepresented among variable transcripts, but those involved in development, transcription regulation, and signal transduction are underrepresented. However, transcripts for proteins known to be involved in protein-protein interactions are proportionally represented among variable transcripts.

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Keywords

additive effects
 
allelic effects
 
cis effects account
 
complex traits
 
different functional categories
 
dominance patterns
 
Drosophila melanogaster
 
equal
 
gene expression
 
genetic variation
 
genetically variable
 
natural population
 
populations
 
protein-protein interactions
 
signal transduction
 
third chromosome causes
 
trans effects
 
trans regulation
 
transcription regulation
 
variable transcripts
 

Kimberly A Hughes